1. Field of the Invention
The present invention relates to a manifold valve used for switching passageways of a pipeline in the chemical plant, semiconductor production, foodmaking, biotech, and other various industrial fields, more particularly related to a manifold valve which enables operation of one valve while disables operation of another valve, is compact, and facilitates installation in and detachment from a pipeline.
2. Description of the Related Art
In the past, in pipelines for semiconductor production, there has been a pipe configuration as shown in FIG. 12 comprised of a main passageway valve 102 for passing and cutting off fluid flowing through a main passageway 101 and a branch valve 104 for opening/closing a branch passageway 103 split off from the main passageway 101. When stopping the flow in the main passageway 101 to replace a part 105 of the pipeline etc., the fluid remaining in the pipeline has been drained outside from the branch passageway 103 so as to enable the part to be replaced without the fluid splattering to the surroundings.
However, in the conventional pipe configuration, when opening the main passageway valve 102 to run fluid through the main passageway 101, the branch valve 104 has to be closed, while when opening the branch valve 104 to run fluid to the branch passageway 103, the main passageway valve 102 has to be closed, but the handles of the valves 102 and 104 were liable to be mistakenly operated. For example, if the fluid were a corrosive fluid and the main passageway valve 102 were closed to replace the part 105 of the pipeline, if mistakenly opening the main passageway valve 102, the fluid flowing through the main passageway 101 would end up splattering to the outside and the worker replacing the part would be liable to be splattered by the corrosive fluid and injured or the splattered fluid would be liable to contaminate or corrode the surroundings of the pipeline and have other detrimental effects.
To solve this problem, a configuration is necessary in which when one valve is operated, another valve can be disabled. As a method for this, there was the opening/closing operation system of a valve as shown in FIG. 13 described in Japanese Patent Publication (A) No. 7-332535. In this configuration, a first pipeline 106 and a second pipeline 107 transporting fluids with different properties are separately provided with a first valve 116 having a first valve element 108 and a second valve 117 having a second valve element 109 angularly displacing about axial lines vertical to the axes of the pipelines 106 and 107 to open and close the passageways of the pipelines 106 and 107. The pipelines 106 and 107 have connected to them a first limiting member 114 and a second limiting member 115 having projecting parts 110 and 112 and recessed parts 111 and 113 in the planes vertical to the axes. The recessed part 111 of one of any two adjoining limiting members 114 and 115 was formed retracted from the path of the projecting part 112 of the other in the angular displacement direction, the recessed part 113 of the other was formed retracted from the path of the projecting part 110 of the one in the angular displacement direction, and the projecting parts 110, 112 of the one and other were formed projecting out into the paths in the angular displacement directions. The effect is that in two pipelines separately transporting fluids of different properties, the second limiting member 115 can only be operated to angularly displace in the state where the projecting part 112 of the second limiting member 115 is fit into the recessed part 111 of the first limiting member 114 and the first limiting member 114 can only be operated to angularly displace in the state where the projecting part 110 of the first limiting member 114 is fit into the recessed part 113 of the second limiting member 115. It is only possible to make the limiting members 114 and 115 with projecting parts 110 and 112 fit into the recessed parts 111 and 113 angularly displace, so it is possible to prevent a plurality of valve elements from ending up being simultaneously opened and the limiting members 114 and 115 from being mistakenly operated.
Summarizing the problems to be solved by the invention, in the conventional valve opening/closing operation system, the first limiting member 114 provided at the first valve 116 and the second limiting member 115 provided at the second valve 117 are respectively provided at the first pipeline 106 and the second pipeline 107, so connecting the pipes so that the projecting parts 110 and 112 and the recessed parts 111 and 113 engage requires fine adjustment of the pipe positions. There are therefore the problems that the pipe work is troublesome and time consuming and, when detaching one valve, the other valve gets in the way, so detachment becomes difficult. Further, when used for pipelines in a semiconductor production system etc., there are the problems that the first limiting member 114 and the second limiting member 115 are not suitable for use in cramped spaces since they take up room and that the first valve 116 and the second valve 117 are ball valves or cocks or other rotary valves, so are not suited to applications where particle formation is averred.